为进一步探索高蛋白大豆最优施肥模式组合,获得高蛋白大豆最佳经济效益。以高蛋白大豆‘冀豆12’为供试材料,对氮、磷、钾三因素分别设置3个处理,以不同氮、磷、钾施用量为自变量,以相应大豆经济效益为依变量,采用正交多项式回归方法,建立高蛋白大豆经济效益预测模型方程,并对各项进行显著性(F)检验。结果表明：钾磷肥只有在氮肥达到一定水平(60~90 kg/hm²)才能更好的发挥肥效作用;施钾量过低或过高均不利于大豆经济效益值的增加;在施磷量50~110 kg/hm²水平间,大豆经济效益值与施磷量基本呈正相关关系。经F检验,氮肥对高蛋白大豆经济效益影响最大,其次为磷,钾效应最小。方差估计值$\hat{\sigma }$=134.5508,预报高蛋白大豆每公顷经济效益$\hat{W}$的95%的置信区间为$\hat{W}$±1.96s=W±263.7196,预测效果较好;模型拟合下氮钾磷施用分别为54.67,62.38,140 kg/hm²,大豆经济效益最高,为13276.13元/hm²。多元正交多项式回归模型对预测多因素施肥水平下高蛋白大豆经济效益有实际参考价值。

The purpose is to further explore the optimal fertilization pattern combination of high-protein soybean and obtain the best economic benefit. The high-protein soybean ‘Jidou 12’ was used as the test material, and three treatments were set for nitrogen, phosphorus and potassium. With different application amounts of nitrogen, phosphorus and potassium as independent variables and the corresponding soybean economic benefits as dependent variables, the orthogonal polynomial regression method was used to establish the economic benefit prediction model equation of high-protein soybean, and the significance (F) test was carried out for each item. The results showed that potassium and phosphate fertilizer could play a better role in fertilizer efficiency only when nitrogen fertilizer reached a certain level (60-90 kg/hm²). Too low or too high potassium application was not conducive to the increase of soybean economic benefit value. The economic benefit of soybean was positively correlated with the amount of phosphorus applied between 50 and 110 kg/hm². According to F test, nitrogen fertilizer had the largest effect on the economic benefit of high-protein soybean, followed by phosphorus and potassium. The estimated variance was $\hat{\sigma }$=134.5508, and the 95% confidence interval of economic benefit per hectare of high-protein soybean was predicted to be $\hat{W}$±1.96s=W±263.7196, and the prediction effect was better. Under the model fitting, the application rate of nitrogen, potassium and phosphorus was 54.67, 62.38 and 140 kg/hm², respectively, with the highest soybean economic benefit of 13276.13yuan/hm². The multivariate orthogonal polynomial regression model has practical reference value for predicting the economic benefit of high-protein soybean under multi-factor fertilization.